RE: kombat 96 and 94
At 84 kg I've found the 96 Kombat an excellent board for the varied conditions I sail locally. Here is my experience with the board.
RE: sail size: My preferred sail is 5.3 at 20-25 knots (footstraps in or outboard) I've sailed 4.7 in 30++ knots though the board/sail is clearly a bit big. Moving the mast forward in the track makes a big difference for board control in the upper end of the range. Sailing 25-30 knots with a 4.7 & the mast forward is nice tough typically others are sailing smaller boards. I estimate I can get going in 15-16 knots steady wind with a 6.4.
Re fin size: The 2006 comes with 2 fins. The fin somewhat relates to footstrap position. Also, I've found the board requires less fin than my previous wave board.
For my summer sailing the footstraps are generally outboard so only the big freeride fin works. The wave fin does not work in this set-up (even with a smaller sail) as there is too much side pressure. The board is very nice with the 30.5 fin in 15-20 knots free-ride conditions with a 6.4. In this set-up, you make good use of the fin. The big fin also works well with the 5.3 up to around 25 knots. When maxed out on the 5.3, a smaller free-ride or B&J fin (or the 2007 cross-over) would be better.
For winter storm sailing the footstraps are generally in-board. The wave fin works fine with the 4.7 & 5.3 for sailing in swell & steep ramps (I don't get on-shore breaking waves). Unless slightly under-powered, there is no problem staying upwind. Due to weeds, I commonly use a weed fin which is bigger & helps if the winds are a bit light. I suspect that the 2007 cross-over fin would be ideal (when there aren't weeds). I've rarely used the 6.4 in winter. Generally, I've found with this big sail, you want the footstraps outboard.
For me at my wieght, the board is the right size as I most often use 5.3 & 6.4. This sail gap is fine with this board. This board is awesome. Hope this helps!